
Microbiomes—the communities of microorganisms such as bacteria, fungi, and viruses residing in and on various parts of animals and humans and in the environment—are integral to health and disease. In recent years, significant advances have been made in understanding the human microbiome. However, a growing area of research is exploring the microbiomes of pets and the complex relationships shared with the microbiomes of their human counterparts. For veterinary professionals, this interconnected microbiome frontier holds profound implications for both animal and human health.





Human microbiomes are primarily concentrated in various body niches, including the gastrointestinal (GI) tract, skin, oral cavity, and respiratory system. These microbiomes influence numerous aspects of health, from digestion and nutrient absorption to immune system modulation and pathogen defense. Dysbiosis, or the imbalance of microbiota, is linked to a variety of conditions such as inflammatory bowel disease, allergies, and even mental health issues.


Similarly, pets, particularly dogs and cats, harbor diverse microbiomes that are crucial for their overall health. The GI tract of pets is home to complex microbial communities that aid in digestion, nutrient absorption, and immune function. Skin and oral microbiomes play protective roles against pathogenic bacteria infections,

 and maintaining homeostasis of the skin and oral cavities.

 Understanding pet microbiomes can provide insights into common veterinary conditions such as allergies, GI disorders, and skin infections.





Pets and humans share several microbiome-associated phenotypes such as obesity, gastric inflammation, and chronic kidney disease. On the other hand, there are microbiome-relevant characteristics special to each host, such as their unique nutritional requirements. For instance, companion animals do not rely on the microbiome for energy production the way humans do, and cats require more protein in their foods compared with dogs and humans, who consume more omnivorous diets.

 The microbial communities that assemble in each host environment have evolved to adapt to that host’s physiology and food intake while also playing a role in modulating host processes such as disease and metabolism. Although there are common microbial members residing in the gut microbiome of cats, dogs, and humans, there are also microbial species unique to each host.

 Some microbial species that are present in both companion animals and humans carry different genes, which may enable them to perform different metabolic or protective functions. This indicates host-specific evolution of microbes to thrive and contribute tailored functionality to each host.





Although the amount may differ from one individual to another, it is common for people in the modern era to spend more than 90% of their time indoors.

 Humans often share the same living environment with their pets, facilitating the exchange of microbes. Findings from studies have shown that pet owners often share more microbial similarities with pets in their household compared with pets in other households.

 This bidirectional transfer occurs through direct contact, shared surfaces, and even the air.

Companion animals can also be carriers of environmental microbial species, especially those who live both indoors and outdoors. One study looked at the microbial composition in the home environment in homes with dogs, cats, or no pets.

 The homes that had dogs had increased microbial diversity when compared with homes with no pets, and homes with cats fell in the middle in bacterial diversity and richness.

 This makes sense considering the vast majority of cats spend their time indoors and are not exposed to additional types of bacteria in the outdoor environment.

Often, when we think about the exchange of microbes, we think about the transmission of pathogenic strains such as Clostridioides difficile, Campylobacter spp, or Escherichia coli.

 However, the transmission of commensals, the beneficial or neutral resident microbes, between humans and pets is an emerging field of study due to the potential positive effects of microbe sharing.





Sharing microbiomes has potential health implications. Pets can contribute beneficial microbes that enhance human microbiome diversity, potentially offering protective benefits against certain diseases.

 Conversely, pets can also be carriers of pathogenic microbes. Findings from one study discovered that bacterial species causing periodontal disease in the mouth could be transmitted between dogs and humans.

 As a result, a balanced approach to pet ownership and hygiene is essential.





There is compelling evidence to suggest that early-life exposure to pets can influence the human microbiome in ways that reduce the risk of allergies, otherwise referred to as immunological priming or the hygiene hypothesis.

 Pet ownership, particularly of dogs, has been associated with a decreased prevalence of asthma and allergic diseases in children.

 This protective effect is thought to be mediated by microbiome-induced immune modulation. Children who lived with pets in the household had higher microbial diversity of their gut microbiome.

 On the other hand, children who developed asthma by the age of 7 years had a low total diversity of the gut microbiota during their first month of life when compared with children who did not develop asthma.

 Therefore, early-life exposure to pets appears to play a role in shaping the human microbiome and potentially lowering the risk of developing allergies and asthma.





The One Health concept emphasizes the interconnectedness of human, animal, and environmental health, with a growing focus on microbiome research. Scientists are investigating how our shared environment affects health, including the roles that pets play. This research holds significant therapeutic potential, such as developing probiotics, prebiotics, and other microbiome therapies such as the use of postbiotics or metabolic products, to enhance human and pet health. It also informs better hygiene and pet care practices, thereby reducing disease transmission risks and amplifying health benefits for both humans and pets. However, close human-pet contact can promote the exchange of antibiotic-resistant bacteria, resulting in hard-to-treat infections.

 This underscores the importance of careful antibiotic use in both human and veterinary medicine. By understanding these dynamics, strategies can be devised to control the spread of resistant bacteria, preserve antibiotic effectiveness, and protect the health of both humans and their pets through focused interventions.





More extensive and detailed profiles of pet microbiomes across different species and breeds are essential to understanding the full scope of their role in health and disease. Microbiome sequencing, combined with specific experiments, can answer many important questions about pet health. These include:

What external factors affect the pet’s microbiome?

How do these factors change the variety and balance of microbes?

How do different microbes move and spread between the pet and their owner?

Which specific microbes or groups of microbes are important for keeping pets and their owners healthy?


Advances in sequencing technologies and bioinformatics will be pivotal in the effort to answer these questions in our quest to better care for our pets.




Long-term studies tracking the microbiomes of pets and their owners can provide deeper insights into how these microbial communities coevolve and influence health over time. Such research may identify key microbial markers associated with disease prevention or progression.





The intricate relationship between human and pet microbiomes represents a fascinating and highly relevant area of study for veterinary professionals. This interconnected microbial world not only influences the health of pets and their owners but also opens up new avenues for preventive and therapeutic strategies. By embracing this holistic perspective, veterinarians will be able to enhance animal care and contribute to the broader understanding of microbiome health across species. The journey into the enigmatic realm of microbiomes is just beginning, and it promises to bring transformative possibilities for both veterinary and human medicine.






1. Mitrea L, Nemeş SA, Szabo K, Teleky BE, Vodnar DC. Guts imbalance imbalances the brain: a review of gut microbiota association with neurological and psychiatric disorders. 

. 2022;9:813204.

2. Bartnicka D, Gonzalez-Gonzalez M, Sykut J, et al. Candida albicans shields the periodontal killer Porphyromonas gingivalis from recognition by the host immune system and supports the bacterial infection of gingival tissue. 

. 2024;21(6):1984.

3. Grice EA, Segre JA. The skin microbiome. 

. 2011;9(4):244-253.

4. Di Stefano M, Polizzi A, Santonocito S, Romano A, Lombardi T, Isola G. Impact of oral microbiome in periodontal health and periodontitis: a critical review on prevention and treatment. 

. 2022;23(9):5142.

5. Palmer RA, Friedmann PS. Ultraviolet radiation causes less immunosuppression in patients with polymorphic light eruption than in controls. 

. 2004;122(2):291-294.

6. McBain AJ, O’Neill CA, Amezquita A, et al. Consumer safety considerations of skin and oral microbiome perturbation. 

. 2019;32(4):e00051-19.

7. Deng P, Swanson KS. Gut microbiota of humans, dogs and cats: current knowledge and future opportunities and challenges. 

. 2015;113(suppl):S6-S17.

8. Branck T, Hu Z, Nickols WA, et al. Comprehensive profile of the companion animal gut microbiome integrating reference-based and reference-free methods. 

. 2024;18(1):wrae201.

9. Klepeis NE, Nelson WC, Ott WR, et al. The National Human Activity Pattern Survey (NHAPS): a resource for assessing exposure to environmental pollutants. 

. 2001;11(3):231-252.

10. Song SJ, Lauber C, Costello EK, et al. Cohabiting family members share microbiota with one another and with their dogs. 

. 2013;2:e00458.

11. Coelho LP, Kultima JR, Costea PI, et al. Similarity of the dog and human gut microbiomes in gene content and response to diet. 

. 2018;6(1):72.

12. Fujimura KE, Johnson CC, Ownby DR, et al. Man’s best friend? the effect of pet ownership on house dust microbial communities. 

. 2010;126(2):410-412.e1-3.

13. Gras LM, Smid JH, Wagenaar JA, et al. Increased risk for Campylobacter jejuni and C. coli infection of pet origin in dog owners and evidence for genetic association between strains causing infection in humans and their pets. 

. 2013;141(12):2526-2535.

14. Rabold D, Espelage W, Abu Sin M, et al. The zoonotic potential of Clostridium difficile from small companion animals and their owners. 

. 2018;13(2):e0193411.

15. Damborg P, Nielsen SS, Guardabassi L. Escherichia coli shedding patterns in humans and dogs: insights into within-household transmission of phylotypes associated with urinary tract infections. 

. 2009;137(10):1457-1464.

16. Salas Garcia MC, Schorr AR, Arnold W, Fei N, Gilbert JA. Pets as a novel microbiome-based therapy. In: Ramiro Pastorinho M, Sousa ACA, eds. 

Pets as Sentinels, Forecasters and Promoters of Human Health

. Springer; 2019:245-267.

17. Yamasaki Y, Nomura R, Nakano K, et al. Distribution of periodontopathic bacterial species in dogs and their owners. 

. 2012;57(9):1183-1188.

18. Azad MB, Konya T, Maughan H, et al. Infant gut microbiota and the hygiene hypothesis of allergic disease: impact of household pets and siblings on microbiota composition and diversity. 

. 2013;9(1):15.

19. Hesselmar B, Hicke-Roberts A, Lundell AC, et al. Pet-keeping in early life reduces the risk of allergy in a dose-dependent fashion. 

. 2018;13(12):e0208472.

20. Tun HM, Konya T, Takaro TK, et al. Exposure to household furry pets influences the gut microbiota of infants at 3-4 months following various birth scenarios. 

. 2017;5(1):40.

21. Abrahamsson TR, Jakobsson HE, Andersson AF, Björkstén B, Engstrand L, Jenmalm MC. Low gut microbiota diversity in early infancy precedes asthma at school age. 

. 2014;44(6):842-850.

22. Ma LC, Zhao HQ, Wu LB, Cheng ZI, Liu C. Impact of the microbiome on human, animal, and environmental health from a One Health perspective. 

Articles

The intricate relationship between human and pet microbiomes represents a fascinating and highly relevant area of study for veterinary professionals. 

Exploring the interconnected world: The relationship between human and pet microbiomes

We are seeing younger, successful owners selling their practices so what do you think is driving this trend and why is it a myth that selling your practice is only for those "older"  or "ready to retire?" 

It's a great question and we are seeing much younger practice owners looking to sell nowadays. With Transitions Elite, the youngest we worked with is 36 years old. The co-owner was 39 years old. What was really driving them was they came to the conclusion after they stood back one day and really asked themselves, "why?" They had thriving multiple locations and everything was going well. They were comfortable. They had to ask, "how much money did they need to make? How many sacrifices do we need to make? We have young families. What is our why? Is this it? Is this all we can expect for the next 20 or 30 years?" With these younger people focused on quality of life, when you say to them that with one decision you can have it all. You can still continue to be a veterinarian, but have much greater job satisfaction if you sell....Quality of life is really what is driving them.

Podcasts

Melani Seymour sits down with Adam Christman, DVM, MBA, to talk about a shift happening in younger veterinary practice owners.



Increasing job satisfaction in the veterinary field

Neil Mittelman, DVM, DACVIM, talks about how to differentiate Schiff-Sherrington from other postures and offers insight into lecture “Recognize, Localize, & Save Lives!”

Recognizing neurological postures

, at the Fetch dvm360 conference in Atlantic City, New Jersey this fall, Neil Mittelman, DVM, DACVIM, talked about his case-based lecture “Recognize, Localize, & Save Lives!” which uses real-life examples of cases with uncommon or odd neurological presentations. Mittelman emphasized the importance of recognizing postures that are related to intracranial pressure and possible brain herniation. He also explained what a decerebrate posture is and offered advice for differentiating between different types of postures.

This is basically a case-based description lecture using real life examples of cases with odd or uncommon presentations, as well as those that are critically important to evaluate. So, certain postures are associated with intracranial pressure changes, possible brain herniation, and these need to be recognized as soon as possible, so we can promptly help them with lifesaving medications.

Videos

Veterinary professionals who are Fear Free certified will be able to better monitor their patient’s health virtually with Maven Pet’s services. Maven Pet, a pet wellness brand that utilizes artificial intelligence to offer pet health monitoring, is partnering with Fear Free—an organization focused on alleviating fear and anxiety in pets by providing certified veterinary care and implementing pet-friendly practices, according to a news release by Maven Pet.

Maven Pet can collect and monitor pet data while flagging irregularities. Meanwhile, Fear Free, which was developed by specialists in behavior, medicine, and handing, provides virtual and in-person tools and education to veterinary professionals and the pet care community that will help them care for pets’ physical and emotional wellbeing.

With the new collaboration, Maven Pet will be included in the Fear Free Preferred Product Program (PPP), which aims to offer Fear Free Certified Professionals access to products and services that support Fear Free’s protocols, procedures, and recommendations.

 Current products and services included in the PPP are targeted pulsed electromagnetic field therapy products, hospital mats, pet kennels and beds, and more. These products and services will facilitate the process of implementing Fear Free in their practice, according to Fear Free.

Through its new contribution to Fear Free’s program, those who are Fear Free Certified will have access to Maven Pet’s services, which will help veterinary professionals get earlier patient diagnoses with the company’s remote monitoring, as well as improve their ability to offer “proactive care without causing the animals any unnecessary stress or trauma,” according to Maven Pet.

 These professionals will be able to monitor their patient’s activity, rest, respiratory rate, water intake, scratching and more. “This approach leads to earlier diagnoses, more effective treatment strategies and better outcomes,” wrote Maven Pet in the release.

“We are thrilled to join forces with Fear Free and become part of a network dedicated to making pet care more comfortable and less stressful,” Guilherme Coelho, CEO of Maven Pet, said in a company release.

“We completely align with Fear Free's vision for a future where pets lead healthier and happier lives, and hope to empower pet parents and veterinarians alike with the tools to make it happen.”

The new collaboration with Fear Free will also benefit pet owners, as Maven Pet’s technology will be able to help them track their pet’s health status without having to worry about creating a stressful and negative experience for their pet, according to Maven Pet.

Maven Pet and Fear Free join forces for stress-free pet health monitoring. News release. 

. November 2024. Accessed December 5, 2024. [email]

Fear Free Preferred Product. Fear Free, LLC. Accessed December 5, 2024. 

https://fearfreepets.com/resources/preferred-product-program/

Maven Pet is partnering with Fear Free to bring veterinary teams AI that monitors patient health

Virtual health monitoring for Fear Free Certified veterinary professionals

Mark J. Acierno, DVM, MBA, DACVIM, talks about his lecture “Leptospirosis: Current Recommendations and What is the Risk to Veterinary Professionals”

Leptospirosis in dogs and vets

Earlier this fall, Mark J. Acierno, DVM, MBA, DACVIM, sat down with 

 during dvm360's Fetch Coastal conference in Atlantic City, New Jersey, to talk about his lecture “Leptospirosis: Current Recommendations and What is the Risk to Veterinary Professionals.” During the interview, Acierno shared topics covered in his lecture as well as debunked the myth that only outdoor dogs in rural areas should be vaccinated for leptospirosis. He explained that small dogs in urban environments are at equal or greater risk of contracting the disease as their rural counterparts. 

In the interview, Acierno also explained that some veterinarians have contracted the infection without realizing it, as most dogs with leptospirosis do not exhibit any signs.

 …We go on and we also talk about the risk to the veterinary professional. For example, at one [American Veterinary Medical Association] meeting, they found that a percentage of veterinarians had actually been seropositive for leptospirosis since they were exposed, probably from one of their patients. And interestingly, none of the people who tested positive thought that they had dealt with a dog with leptospirosis. …They had seen a dog with flu-like symptoms, and then shortly thereafter, these veterinarians got headaches, but they didn't realize that the patient had [leptospirosis] and that they had contracted it from their patient. And part of that is, is that when we look at dogs that are experimentally and even naturally infected with leptospirosis, you know, we think about the liver disease and the kidney disease and some of the other things that we see, like anemia and thrombocytopenia.

But in reality, most dogs that are exposed to leptospirosis and are shedding it, don't really have many signs at all. They often are described as having flu-like symptoms. And so, we need to kind of broaden our perception of who we should be suspecting of having leptospirosis.

Grey Wolf Animal Health Corp, a diversified health care company based in Toronto, Canada, has acquired the Compounding Pharmacy of Manitoba (CPM) for $22.5 million. The acquisition includes associated real estate, pursuant to a Share Purchase Agreement, according to a news release.

The independent CPM is based in Oakbank, Manitoba. The facility spans 25,000 sq ft and serves independent and corporate-owned pharmacies, as well as veterinarians in Canada. This facility is anticipated to improve Grey Wolf’s capacity for growth in their pharmacy business unit. The acquisition is also expected to diversify the company’s customer mix and expand into the veterinary and human compounding markets.

CPM generated an estimated $6.4 million and approximately $2.5 million in adjusted earnings before interest, taxes, depreciation, and amortization over the 12 months ending September 30, 2024, according to a news release.

 At the time of the agreement, Grey Wolf paid $19.8 million in cash and issued 3,160,112 shares of its stock, valued at $0.8544 per share. The cash payment was funded using Grey Wolf's existing cash reserves and 2 new loans totaling $18.7 million from its current lender. Grey Wolf’s new purchase is “expected to be immediately accretive to revenue.”

"We believe CPM is complementary to our Trutina acquisition that we completed in 2021 and provides the ability to expand our existing business in both the veterinarian and human compounding pharmacy markets from a new facility near Winnipeg" Angela Cechetto, CEO of Grey Wolf, said in the company news release.

 Trutina is a Canadian compounding pharmacy that formulates medication for veterinary and human patients.

In 2022, the global market for animal drug compounding was valued at 1.3 billion USD. It is projected to grow at a compound annual growth rate (CAGR) of 8.19% during the forecast period. Contributing factors of its growth include increasing awareness among pet owners of the benefits of compounded medications, causing more pet owners to purchase these personalized medications.

Demand for compounded medications for companion animals is leading the market growth, with felines contributing a significant portion of that growth. Medicating cats can be difficult, creating a demand for compounded medications in feline medicine that ensures patient compliance during administration while maintaining the human-animal bond.

 According to the FDA, veterinarians in the United States prescribe 6.3 million compounded animal drug prescriptions annually.

Grey Wolf Animal Health announces the acquisition of the Compounding Pharmacy of Manitoba. News release. Grey World Animal Health Corp. December 2, 2024. Accessed December 5, 2024. 

https://www.newswire.ca/news-releases/grey-wolf-animal-health-announces-the-acquisition-of-the-compounding-pharmacy-of-manitoba-899223148.html

Trutina Pharmacy. Trutina Pharmacy. Accessed December 5, 2024. 

Animal Drug Compounding Market Size, Share & Trends Analysis Report By Animal Type (Companion Animals, Livestock Animals), By Product, By Route of Administration, By Dosage Form, By Region, And Segment Forecasts, 2023 – 2030. Grand View Research. Accessed December 5, 2024. 

https://www.grandviewresearch.com/industry-analysis/animal-drug-compounding-market-report

Grey Wolf Animal Health Corp recently acquired the Compounding Pharmacy of Manitoba